Precision measurement of the microwave dielectric loss of sapphire in
the quantum regime with parts-per-billion sensitivity
- URL: http://arxiv.org/abs/2206.14334v2
- Date: Mon, 1 May 2023 03:24:15 GMT
- Title: Precision measurement of the microwave dielectric loss of sapphire in
the quantum regime with parts-per-billion sensitivity
- Authors: Alexander P. Read, Benjamin J. Chapman, Chan U Lei, Jacob C. Curtis,
Suhas Ganjam, Lev Krayzman, Luigi Frunzio, Robert J. Schoelkopf
- Abstract summary: Dielectric loss is known to limit state-of-the-art superconducting qubit lifetimes.
Recent experiments imply upper bounds on bulk dielectric loss tangents on the order of $100$ parts-per-billion.
We have devised a measurement method capable of separating and resolving bulk dielectric loss with a sensitivity at the level of $5$ parts per billion.
- Score: 50.591267188664666
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Dielectric loss is known to limit state-of-the-art superconducting qubit
lifetimes. Recent experiments imply upper bounds on bulk dielectric loss
tangents on the order of $100$ parts-per-billion, but because these inferences
are drawn from fully fabricated devices with many loss channels, they do not
definitively implicate or exonerate the dielectric. To resolve this ambiguity,
we have devised a measurement method capable of separating and resolving bulk
dielectric loss with a sensitivity at the level of $5$ parts per billion. The
method, which we call the dielectric dipper, involves the in-situ insertion of
a dielectric sample into a high-quality microwave cavity mode. Smoothly varying
the sample's participation in the cavity mode enables a differential
measurement of the sample's dielectric loss tangent. The dielectric dipper can
probe the low-power behavior of dielectrics at cryogenic temperatures, and does
so without the need for any lithographic process, enabling controlled
comparisons of substrate materials and processing techniques. We demonstrate
the method with measurements of EFG sapphire, from which we infer a bulk loss
tangent of $62(7) \times 10^{-9}$ and a substrate-air interface loss tangent of
$12(2) \times 10^{-4}$. For a typical transmon, this bulk loss tangent would
limit device quality factors to less than $20$ million, suggesting that bulk
loss is likely the dominant loss mechanism in the longest-lived transmons on
sapphire. We also demonstrate this method on HEMEX sapphire and bound its bulk
loss tangent to be less than $15(5) \times 10^{-9}$. As this bound is about 3
times smaller than the bulk loss tangent of EFG sapphire, use of HEMEX sapphire
as a substrate would lift the bulk dielectric coherence limit of a typical
transmon qubit to several milliseconds.
Related papers
- Dielectric Loss due to Charged-Defect Acoustic Phonon Emission [0.0]
Loss per defect depends mainly on properties of the host material.
Diamond, cubic BN, AlN, and SiC are optimal in this respect.
arXiv Detail & Related papers (2024-02-27T08:10:18Z) - Model-based Optimization of Superconducting Qubit Readout [59.992881941624965]
We demonstrate model-based readout optimization for superconducting qubits.
We observe 1.5% error per qubit with a 500ns end-to-end duration and minimal excess reset error from residual resonator photons.
This technique can scale to hundreds of qubits and be used to enhance the performance of error-correcting codes and near-term applications.
arXiv Detail & Related papers (2023-08-03T23:30:56Z) - Improved Coherence in Optically-Defined Niobium Trilayer Junction Qubits [45.786749852292246]
Niobium offers the benefit of increased operating temperatures and frequencies for superconducting devices.
We revisit niobium trilayer junctions and fabricate all-niobium transmons using only optical lithography.
We characterize devices in the microwave domain, measuring coherence times up to $62mu$s and an average qubit quality factor above $105$.
arXiv Detail & Related papers (2023-06-09T13:26:13Z) - Disentangling superconductor and dielectric microwave losses in
sub-micron $\rm Nb$/$\rm TEOS-SiO_2$ interconnects using a multi-mode
microstrip resonator [0.0]
Investigation of the origins of power loss in superconducting interconnects is essential for the energy efficiency and scalability of superconducting digital logic.
A novel method to accurately disentangle such losses is described using a multi-mode transmission line resonator.
arXiv Detail & Related papers (2023-03-19T15:13:45Z) - Millikelvin measurements of permittivity and loss tangent of lithium
niobate [50.591267188664666]
Lithium niobate is an electro-optic material with many applications in microwave signal processing, communication, quantum sensing, and quantum computing.
We present findings on evaluating the complex electromagnetic permittivity of lithium niobate at millikelvin temperatures.
arXiv Detail & Related papers (2023-02-24T22:05:42Z) - Compact vacuum gap transmon qubits: Selective and sensitive probes for
superconductor surface losses [0.0]
State-of-the-art transmon qubits rely on large capacitors which systematically improves their coherence.
We present transmon qubits with sizes as low as 36$ times $39$ mu$m$2$ with $gtrsim$100 nm wide vacuum gap capacitors.
arXiv Detail & Related papers (2022-06-28T16:02:08Z) - Measurement of the Low-temperature Loss Tangent of High-resistivity
Silicon with a High Q-factor Superconducting Resonator [58.720142291102135]
We present the direct loss tangent measurement of a high-resist intrinsicivity (100) silicon wafer in the temperature range from 70 mK to 1 K.
The measurement was performed using a technique that takes advantage of a high quality factor superconducting niobium resonator.
arXiv Detail & Related papers (2021-08-19T20:13:07Z) - In-situ bandaged Josephson junctions for superconducting quantum
processors [101.18253437732933]
Shadow evaporation is commonly used to micro-fabricate the key element of superconducting qubits - the Josephson junction.
Here, we present an improved shadow evaporation technique allowing one to fabricate sub-micrometer-sized Josephson junctions together with bandage layers in a single lithography step.
arXiv Detail & Related papers (2021-01-05T11:08:09Z) - Investigation of microwave loss induced by oxide regrowth in high-Q Nb
resonators [0.0]
We study niobium resonators after removing the native oxides with a hydrofluoric acid etch.
We find that losses in quantum devices are reduced by an order of magnitude, with internal Q-factors reaching up to 7 $cdot$ 10$6$ in the single photon regime.
Our findings are of particular interest for devices spanning from superconducting qubits, quantum-limited amplifiers, microwave kinetic inductance detectors to single photon detectors.
arXiv Detail & Related papers (2020-12-19T19:14:19Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.